I have a new win 10 PC want to change active background as to bright to light grey

[Windows Central Question]

Win 7 Vista XP can change active background in themes so for example when you open office prog 2007 you have a grey not white worksheet

I have sensitive eyes white is to bright Help

 

[Cryio]

Is this a Windows or Office request? Because Office 2016 does have a dark theme.